The present invention relates in general to an apparatus and method for mixing and injecting or applying an epoxy or viscous blend and more particularly to an apparatus which is capable of repeatedly mixing, delivering, and injecting or applying a preprogrammed amount of highly viscous two or more part epoxy which may contain strengthening or reinforcement fibers. The present invention represents a system for optimal delivery of the epoxy blend including heated holding tanks with auger feeds, a variable ratio pump capable of pumping highly viscous epoxy resin and hardener, and a unique dispensing and mixing head which is utilized as a part of the system. The apparatus is capable of mixing and delivering a preprogrammed quantity of epoxy mix in a very short period of time.
Epoxy is a common compound usually comprised of a hardener or curing agent and a resin which is often used as an adhesive and also to fill or seal gaps, holes, or cavities within a structure. Often, a fibrous reinforcing material is added to the blend to improve strength and durability. It has found wide use within the industrial, residential, and commercial sectors. One of the many industrial uses for epoxy includes the filling of holes or cavities in railroad ties and more particularly the filling of voids in railroad ties caused by rail seat abrasion. Rail seat abrasion represents an erosion or wearing of the railroad tie at the interface between the railroad rail and the tie. This phenomena is especially true for concrete railroad ties. That is, the movement of the railroad rail on the concrete tie during use causes a groove to wear into the tie. Stability of the rail necessitates repair of the groove by filling said groove with a strong and environmentally durable material. Typically, an epoxy and fiber mixture is placed into said groove and a rubber pad is placed between the rail and said epoxy mixture for complete repair and filling of said rail seat abrasion.
To date, large scale use of an epoxy resin as aforementioned has been difficult due to the highly viscous nature of said epoxy and the difficulty of feeding fibers with the epoxy. That is, a highly viscous material is difficult to pump, feed, mix, and deliver in a short amount of time and further presents difficulties controlling the exact ratio of mixture delivered. Furthermore, when fibers are added to the epoxy mixture, traditional feeding, valving, and mixing mechanisms tend to fail when the fibers accumulate and jam around said mechanisms.
As intimated, epoxy is formed from a highly viscous epoxy resin and a hardener typically mixed in a ratio of 1:0.5 to 1:2.0 respectively. Precise control of said mixing for such highly viscous materials is difficult due to unpredictable hose expansion and control of pump synchronization at the pressures necessary for delivery of the viscous epoxy. Prior to the art of the present invention, the mixing and delivering devices had a minimal amount of control over the quantity of resin and hardener delivered and were unreliable when fiber reinforcement material was added. With prior art devices, the user could not be assured that the same preprogrammed epoxy mixture amount could or would be delivered for every shot or use of the device. A further prior art problem is represented by the excessive amount of time which was necessary to deliver a preprogrammed amount of mixed epoxy. Ideally, the epoxy mixture should be delivered nearly instantaneously with the desired mixture of resin and hardener. Also, at the pressures necessary to flow such highly viscous materials, apparatus safety has continually been of concern.
The present art overcomes the aforementioned prior art limitations by providing an apparatus, system, and method for mixing, delivering, and injecting or applying a preprogrammed and repeatable amount of the aforementioned epoxy mixture in a short period of time from a dispensing or mixing head which delivers and mixes the epoxy. The present art utilizes uniquely heated storage and feed tanks for reducing the viscosity and improving cure time of the epoxy constituents and a unique variable ratio pump with spring loaded or biased suction and discharge port check valves to assure quick and repeatable delivery of the epoxy mixture. It further utilizes a unique combination of components which function reliably when a fiber reinforcement material is placed within said epoxy mixture.
Accordingly, it is an object of the present invention to provide a method, system, and apparatus for optimally mixing, injecting, or applying a two or more part epoxy which is capable of delivering a repeatable and programmed amount of epoxy into or onto a hole, cavity, or groove.
Another object of the present invention is to provide a method, system, and apparatus for optimally mixing and injecting a two part epoxy which is capable of mobility on railroad tracks and on railroad ties when a rail has been removed.
A further object of the present invention is to provide a method, system, and device for optimally mixing and injecting or applying a two part epoxy which delivers the epoxy mixture quickly.
A still further object of the present invention is to provide a dispensing or mixing head as an integral part of the present art apparatus which provides the aforementioned advantages and is designed to work in conjunction with the present art apparatus.
A yet further object of the present invention is to provide a unique method of thinning and feeding the constituent parts of the epoxy blend through the use of uniformly heated tanks having auger feeds.
A further object of the present invention is to provide a variable ratio dual pump mechanism capable of continuous pumping action in both extension and reflex with unique spring loaded or biased check valves in the suction and discharge ports of said mechanism for precise mixture control.
A further object of the present invention is to provide a method, system, and apparatus for optimally mixing and injecting or applying a highly viscous material which may contain fibrous material in a safe and reliable manner.